Electrically-heated soldering-iron.



LW. CAMPBELL. ELEGTRIGALLY HEATED SOLDERING IRON.' ."LPPLICATIXl FILED J'AN, 1914.' RENEWED DEU. 14, 1914.

LGUIS WILLIAM CMIFEELL, 0F SOUTH YARRA, VCTGE; AUSTRL..

ELECTECALLY-HEATED SOILDERNGRN.

specification of Letters-Patent.

Patented Fen. es i Application filed January 7, 1914,' Serial No.- 810,831, Renewed December le, 1914.' Selsltoj/TS.

T0 all 'whom t may con cem:

Be it known that l, Louis WILLIAM CAMPBELL, of 2.68 Tooralr road, v South Yar'z, in the State ot Victoria, Common- Wealthpf Australia, business representative, have invented certain new and useful Improvements in Electrically-Heated Soldering-honey oi' which the following is a specification.'

This invention relates to improve -ents in electrically heated soldering irons for melting and applying solder to unite adjacent nctallic edges or surfaces and used by plumbers, tinsmiths and other Workers in sheet metal and thelike.

Hitherto 'it has been proposed to construct an electrically heated soldering iron with a copper bit having a bifurcation in vthe rear or handle end `Within which is located the heating unit comprising coils of resistance Wire mounted on a prism or rod` of mica audffuinished with lead and return Wires which are insulated from each other by coverings of beads or the like. The lead and return'wires are covered with a per# iorated tube one end of which is 4connected to the copper bit While. the opposite end is provided with a handle einen-conducting material having a' conveniently operated means for connecting up the 'said Wires Vith supply rines enced with this forni` Ici:j'construction are the loss of heat occasioned by the fact that only part oi `the heating unit is employed to hes't'the bit andthe liability that exists of the beadcovering 'of the Wirebecoming broken` through -rough usag'e.- The heat from the uncovered edges or the heating unit radiate's :into the atmosphere and ris lost-and' should' the bead covering or they Wires become'brolen the 'wires arev liablev tofcontact With each other and useor contact with the perforated metal shield with similarinjurious results.

The present invention has been `devised in order to obviate the above mentioned disadvantages by providingcertain new and useful improvements Which will permit of the utilizationof all the heat :obtained from the unit and` permit of the vlead and return Wires being arranged in such a Way that there is not the least liability of them contacting with each other or With the perforated' metal shield or other portion of the implement. Moreover, the invention is di- .-rec'ted to the provisionof a simple and erence 'will now be 'had to the accompany; nsheet of explanatory drawings, wherein wire l one end'of Which is connected to he 'disadvantages experi j with the bar 2 In order that the-invention together with the mode of corryingthe same into prac-ti cal edect 4may' be readily understood "een Figure l is a View in elevation, partin in sectionyof a soldering iron constructed so cording to the'present invention. 2 i a view illustrating the 'heating unit an` electrical connections, and Figs. 3 to views orn constructional details enibodiedin the invention.

In these drawings thenumeral' l designates a cylindrical rod formed oa plurality of small mica. Washers threaded on a bar Q and held firmly and closely thereon'by' suitable longitudinal or end pressure'. The necessary end pressure can be obtained screwing the bar 2 and using-'nuts 3 or the like clamping means. Over one end o 't rodelthus formed is coiledafhigh resist adjacent end of the bar 2 While the opposite end traverses a groove formed helically in the periphery of andis connected to a metal sleeve 6 fitted rigidly to the Aother end ofthe said rod. Thefends of then/i 4 are voreiterably' fused Where they conne and sleeve 6. i `The rod l with its Winding' oihi sistance Wire i'orins the heating 1* thisunit and-mode of manufaetur same is particularly described in vious application for Letters iatent in t. United States or America Serial llo. We, filed alune '17th. i913. The end or porting rod' l provided With the coils resis ce Wire 'is inserted in a sheath 8 which is adapted to be inserted in ahele formed axially in the-rear end of a copper bit l0 and is insulated therefrom by pape-lring ll of suitable non-conducting niat"isl, preferably mica. A packing l2 similar to l1 is employed to insulate the Wires l 'r un the sides of the sheath 8.

The'sleeve G on the inner end of the rod l is arranged concentrically with the corresponding'end or" the bar 2 and the said bar and sleeve are detachably connected by bar'l and tube 1G, respectively, to a concentric plug 13 screwed to the end of a handle 14. The bar 15 is insulated from the tube-1G by mica 17 or other non-conducth i# to the handle, and there 1s suihcient play 1n ing material which is secured rigidly within the' said tube in an approved way. The 1nner -end of the bar is fitted with a piece of tubing'l which is adapted to -t snugly over 'a connecting jack 19 projecting cen,-

.- trally from the plug 13. Secured to the said plug 13 and concentrically around the connectingl jack 19 is a sleeve 20 which snugly 'engages the. inner end of the tube.

16. The handle 14' is formed of. liber or other v,suitable material and the plug 13 .screws onto the projecting portion of a nip- 4#ple 21 screwed into the handle. The foryward end of the nipple 2l normally lies adjacent to a collar 22 formed on the tube 16l and a recess 23 is formed in the nipple to laccommodate a feather 24 formed on the periphery of the said tube. The feather- 24. and recess 23 prevent the heating unit being revolved whenthe plug 13 is being sorewe of the parts when heated.

' A cap 25 issecured outer end 'of the plug 13 to cover terminals 26 and 27, which are 'connected to the jack the said recess to provide for the expansion 19 and sleeve 20.' .The said cap .forms thel 'end of the handle and the supply wires 28 j pass through a hole 29 in'the end thereof and are secured to the terminals 26 `and 27.

rl"he orwardpart of the handle screws into "a collar 30 1itted rigidly to a piece of perorated tubing 31 and between the said collar and handle is I secured an enlarged washer 32which forms a guard to revent the hand 'slipping forwardly on to t e perforated tubing. V

A flange 33 is formed on the outer end of the perforated tubing 31 and holes are made 'therein to correspond with a hole formed in a flange 3a on the inner end of a sleeve 35. The sleeve-35 is arranged' to pass over the point of-I the blt 10 and the flange 3-1 on the said sleeve` and the i'iange 33 on the tubing are fastened together securelyby bolts 36 or the like passing through the holes'tliere-v in. A piece of asbestos wood 37 or similar non-conducting material is placed between-` the flanges on thetubing and on the sleeve 35'- and is retained in position by the bolts 36. v'The outer end of the sleeve 35 is formed with an inwardly projecting Bange or collar 38. which bears against the outer face of a collar 39 formed on'the bit. The rotation of the bit is prevented by forming a projection 40 thereon which is accommodated 'by a recess 41 in the flange 38 on the.

end of the sleeve 35. The inside zuteiliameter of the sleeve 35 is sufficiently large to permit of it passing freely over the col vlar 39 on the bit and ,consequently an annular air space42 is formed betweenthe two members. The -said airspace l2 forms an insulation that will be found extremely useful for preventing radiation in a lateral terminal 27.

detachably to the I Vdirection and for directing the heat toward.

the points of the bit. i

The sheath S'prevents injury to the heating unit when attaching or detaching a b it and it will pass freely into the hole formed axially in the said bit. The end of the said vsheath is provided with disks -of mica 43 or other non-conducting material to prevent the end of the bar 2-contacting with the said sheath or with the bit. The. sheath 8 for the heating element may be secured to the asbestos or non-conducting material placed between the tubing of the sleeve and lined with sheet micaor other non-conducting material. The lead for the electric current 26, sleeve 20, tube 16, sleeve 6, high resistance wire 4 and the return lead comprises the bar 2, bar .15, tubing 18, jack 19 and for heating the unit comprises the terminal It will be readily obvious that the various parts of the imp ment can be assembled and taken apart easily and quickly andthat as all the parts are accessible they can be readily renewedor replaced when required.

What I do claim is l'. An electrically heated 'soldering iron comprising a b it formed with an axial bore,

a heating element disposed within the bore in said bit, a 4sheath. surrounding said element within said. bore, a perforated tube surrounding. said heating element coaxial with the b ore in said bit, a connection between said bit and tube, a handle'connected with said tube, and means whereby said heatingelement may be energized.

2. An electrically heated soldering iron' comprising a bit having an axia formed therein, a sheath within said bore, a heating element within said sheath, a sleeve surrounding said bito ncentrically of said heating element and sp ced apart from bore,-

the bit whereby an air space is'formed, a

ri'gid connection between said sleeve and bit, a perforated tube surrounding said heating element coaxial' with said sleeve, a connection between said sleeyeandltube, a handle, a detachableconnection between said.

handle and tube,"and means whereby said heating element maybe supplied with cur- Velement coaxial with vsaid sleeve, a connectionbetween said sleeve and tube, a handle, a detaehableconnection between saidy handle and tubo, means whereby said heating element may be supplied with current,'a plugv 1 3@ connected with the outer end of said han'- dle, and connections between said plug and heating e ement whereby-the latter may be connected up with a source of electrical energy.

An electrically heated soldering iron cox'npriing a bit having an axial bore 'foijined therein, a sheath within Said bore, a heating element within said sheath, a.

element whereby the latter ney be connected up with a source of electrical energy, and a cap connected with said plug and inclosing Asaid electrical connections.

5. An electrically heated soldering iron comprising a bit, a sheath within said bit, a heating element 'within said sheath, a sleeve surrounding said bit concentrically thereof, a perforated tube coaxial with said sleeve, a connection between said tube and sleeve, a handle, a detachable connection between said handle and tube, and means whereby said heating element may be supplied with current. w

In testimony whereof l aixmy signatue in presence of two' witnesses. A

LOUIS WILLAM CAMPBELL.

Witnesses:

' A. N. COOKE,1

l/V. A. ASHTON. 

